SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4358810f66d57563f4e8166034bdecdb2c38c2f22b9a8baa0e7801bd90664420' 
  AND token = '/Iq2LVazBIJGpDCXix3v0dIEJ+nRxvLlsFWsQ0LhFnI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}